The victories and milestones just can't come fast enough for American teenager Mikaela Shiffrin. At 17, she's already a world champion _ and the only question now seems to be just how good of a skier she can become.

Shiffrin became the youngest woman in 39 years to win the slalom world title Saturday, shaking off a serious bout of nerves to edge local hope Michaela Kirchgasser out of the lead in front of a partisan crowd of 30,000 fans who were nearly all supporting the Austrian.

Not a bad present ahead of her 18th birthday next month.

"Doing what I did on the hill today, especially in the second run, just skiing, is like dancing or flying," Shiffrin said. "There's so many ways that I can describe it. But it just is, and it works for me.

"It's been 17 years in the making and everybody says that it comes so fast but it seems like it's been forever for me. ... I am just doing what I do and I don't want to wait."

The only slalom world champions younger than Shiffrin were Hanni Wenzel of Liechtenstein in 1974 and Esme Mackinnon of Britain in 1931. Overall, Shiffrin is the youngest women's world champion since fellow American Diann Roffe-Steinrotter, who was 21 days younger when she won the giant slalom title in 1985.

Shiffrin earned her first three career World Cup victories earlier this season to lead the slalom standings and set up big expectations for her first major championship. That explains the nerves before the opening run, in which she placed third.

"My muscles just all morning felt so sluggish and tired like I was still sleeping," she said. "I just couldn't move my feet fast enough. As I got down the run my legs started to wake up."

In between runs, Shiffrin had a hot chocolate and ran around to get her blood flowing.

"And all of sudden two minutes before start I felt my muscles, they were alive," she said. "And my head cleared and all of a sudden it was like a whole new day."

For Shiffrin's mother, Eileen, who was watching from the stands, it wasn't that simple.

"I was nervous because I knew that she said that she couldn't feel her legs before the run," Eileen Shiffrin said. "I am really proud of her. For all the kids out there, here is a lesson _ you can (do) something good even if you are really, really nervous."

After taking the lead in the second run, Shiffrin watched Tanja Poutiainen of Finland and Frida Hansdotter of Sweden each fail to match her time. Shiffrin finished in a combined time of 1 minute, 39.85, with Kirchgasser 0.22 behind in second and Hansdotter third, 0.26 back.

After Hansdotter crossed the finish and Shiffrin realized she had won, the American looked around in disbelief before hugging Kirchgasser several times. Shiffrin's parents Jeff and Eileen embraced each other in the stands, both with tears in their eyes.

During the podium ceremony, Shiffrin breathed heavily but held back tears as she sang the American anthem, with her father videotaping the scene. Shiffrin's brother, Taylor, who is two years older, was also in attendance.

While both of her parents were ski racers, it was when Taylor started to race that Shiffrin realized she, too, wanted to be a part of the sport.

Shiffrin grew up in Colorado and moved to New Hampshire when she was 12, so she started skiing in powder out west then got used to rougher and icier conditions in the northeast.

She credits former U.S. coach Kirk Dwyer for shaping the way she skis while at the Burke Mountain Academy in Vermont. According to mom Eileen, it was Dwyer who discovered that Shiffrin can train "twice as much volume as other kids."

"When other kids would do eight runs Mikaela would do at least 12 and then take three more," said Eileen Shiffrin, who travels the World Cup circuit in Europe with her daughter. "(Shiffrin's current U.S. coach Roland Pfeifer) was surprised when she met her that some of her fastest times would be on her 11th run of a day in a 40-second course. ... She's just always done that. Ever since she was little she would just go until the sun went down."

After earning the first victory of her career in Are, Sweden, in December, Shiffrin became the first American woman to win two World Cup races before the age of 18 by winning in Zagreb, Croatia, early last month. Then in Flachau she added a third victory to match a record set by Austrian legend Annemarie Moser-Proell, who in 1971 was exactly the same age of 17 years, 308 days when she won her third of record 62 races.

Shiffrin is already being called skiing's next big star, with many expecting her one day take over from Lindsey Vonn as the sport's top name.

Vonn is just three wins away from matching Moser-Proell's all-time wins record but had a season-ending crash in her opening event here.

But Shiffrin and her American teammates are already filling the void quite well _ even with Bode Miller sitting this season out to recover from left knee surgery.

Ted Ligety has won three golds at these worlds, and with Shiffrin's victory and a bronze from Julia Mancuso, the U.S. is assured of finishing atop the medals' standings. Ligety could add another medal in Sunday's men's slalom, the final event.